<?php

/**
 * This file is part of the Codizer package.
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 *
 * @copyright   Copyright (c) 2010 Advisa (http://www.advisa.fr)
 * @author      Codizer Core Team <team@codizer.org>
 * @package     Codizer
 */

/**
 * zip file creation class, makes Zip files
 *
 * Based on :
 *
 * http://www.weberdev.com/get_example-4499.html
 * By Hasin Hayder <countdraculla@gmail.com>
 *
 * http://www.zend.com/codex.php?id=535&single=1
 * By Eric Mueller <eric@themepark.com>
 *
 * http://www.zend.com/codex.php?id=470&single=1
 * by Denis125 <webmaster@atlant.ru>
 *
 * a patch from Peter Listiak <mlady@users.sourceforge.net> for last modified
 * date and time of the compressed file
 *
 * Official ZIP file format: http://www.pkware.com/documents/casestudies/APPNOTE.TXT
 *
 */

class f_package_Zip
{
    private $datasec      = array();
    private $ctrl_dir     = array();
    private $eof_ctrl_dir = "\x50\x4b\x05\x06\x00\x00\x00\x00";
    private $old_offset   = 0;

    private function  __construct()
    {
        
    }

    /**
     * @return f_package_Zip
     */
    public static function getInstance()
    {
        return new self();
    }

    /**
     * Converts an Unix timestamp to a four byte DOS date and time format (date in high two bytes, time in low two bytes allowing magnitude comparison).
     *
     * @param integer $unixtime
     * @return integer
     */
    private function unix2DosTime($unixtime = 0)
    {
        $timearray = ($unixtime == 0) ? getdate() : getdate($unixtime);

        if ($timearray['year'] < 1980)
        {
            $timearray['year']    = 1980;
            $timearray['mon']     = 1;
            $timearray['mday']    = 1;
            $timearray['hours']   = 0;
            $timearray['minutes'] = 0;
            $timearray['seconds'] = 0;
        }

        return (($timearray['year'] - 1980) << 25) | ($timearray['mon'] << 21) | ($timearray['mday'] << 16) | ($timearray['hours'] << 11) | ($timearray['minutes'] << 5) | ($timearray['seconds'] >> 1);
    }

    /**
     * Adds an empty directory to the zip file
     *
     * @param string $name
     * @example addDir('myPath/');
     */
    public function addDir($name)
    {
        $name = str_replace("\\", "/", $name);

        $fr = "\x50\x4b\x03\x04";
        $fr .= "\x0a\x00";
        $fr .= "\x00\x00";
        $fr .= "\x00\x00";
        $fr .= "\x00\x00\x00\x00";

        $fr .= pack("V",0);
        $fr .= pack("V",0);
        $fr .= pack("V",0);
        $fr .= pack("v", strlen($name) );
        $fr .= pack("v", 0 );
        $fr .= $name;
        
        $fr .= pack("V",$crc);
        $fr .= pack("V",$c_len);
        $fr .= pack("V",$unc_len);

        $this->datasec[] = $fr;

        $new_offset = strlen(implode("", $this->datasec));

        $cdrec = "\x50\x4b\x01\x02";
        $cdrec .="\x00\x00";
        $cdrec .="\x0a\x00";
        $cdrec .="\x00\x00";
        $cdrec .="\x00\x00";
        $cdrec .="\x00\x00\x00\x00";
        $cdrec .= pack("V",0);
        $cdrec .= pack("V",0);
        $cdrec .= pack("V",0);
        $cdrec .= pack("v", strlen($name) );
        $cdrec .= pack("v", 0 );
        $cdrec .= pack("v", 0 );
        $cdrec .= pack("v", 0 );
        $cdrec .= pack("v", 0 );
        $ext = "\x00\x00\x10\x00";
        $ext = "\xff\xff\xff\xff";
        $cdrec .= pack("V", 16 );

        $cdrec .= pack("V", $this->old_offset);
        $this->old_offset = $new_offset;

        $cdrec .= $name;
        $this->ctrl_dir[] = $cdrec;
    }


    /**
     * Add a file to archive
     *
     * @param string  file contents
     * @param string  name of the file in the archive (may contains the path)
     * @param integer the current timestamp
     *
     */
    public function addFile($data, $name, $time = 0)
    {
        $name     = str_replace('\\', '/', $name);

        $dtime    = dechex($this->unix2DosTime($time));
        $hexdtime = '\x' . $dtime[6] . $dtime[7]
                  . '\x' . $dtime[4] . $dtime[5]
                  . '\x' . $dtime[2] . $dtime[3]
                  . '\x' . $dtime[0] . $dtime[1];
        eval('$hexdtime = "' . $hexdtime . '";');

        $fr   = "\x50\x4b\x03\x04";
        $fr   .= "\x14\x00";
        $fr   .= "\x00\x00";
        $fr   .= "\x08\x00";
        $fr   .= $hexdtime;

        $unc_len = strlen($data);
        $crc     = crc32($data);
        $zdata   = gzcompress($data);
        $zdata   = substr(substr($zdata, 0, strlen($zdata) - 4), 2);
        $c_len   = strlen($zdata);
        $fr      .= pack('V', $crc);
        $fr      .= pack('V', $c_len);
        $fr      .= pack('V', $unc_len);
        $fr      .= pack('v', strlen($name));
        $fr      .= pack('v', 0);
        $fr      .= $name;

        $fr .= $zdata;

        $fr .= pack('V', $crc);
        $fr .= pack('V', $c_len);
        $fr .= pack('V', $unc_len);

        $this->datasec[] = $fr;

        $cdrec = "\x50\x4b\x01\x02";
        $cdrec .= "\x00\x00";
        $cdrec .= "\x14\x00";
        $cdrec .= "\x00\x00";
        $cdrec .= "\x08\x00";
        $cdrec .= $hexdtime;
        $cdrec .= pack('V', $crc);
        $cdrec .= pack('V', $c_len);
        $cdrec .= pack('V', $unc_len);
        $cdrec .= pack('v', strlen($name) );
        $cdrec .= pack('v', 0 );
        $cdrec .= pack('v', 0 );
        $cdrec .= pack('v', 0 );
        $cdrec .= pack('v', 0 );
        $cdrec .= pack('V', 32 );

        $cdrec .= pack('V', $this->old_offset);
        $this -> old_offset += strlen($fr);

        $cdrec .= $name;

        $this -> ctrl_dir[] = $cdrec;
    }


    /**
     * Dumps out generated zip file
     *
     * @return string the zipped file content
     */
    private function file()
    {
        $data    = implode('', $this->datasec);
        $ctrldir = implode('', $this->ctrl_dir);

        return
            $data .
            $ctrldir .
            $this->eof_ctrl_dir .
            pack('v', sizeof($this->ctrl_dir)) .
            pack('v', sizeof($this->ctrl_dir)) .
            pack('V', strlen($ctrldir)) .       
            pack('V', strlen($data)) .          
            "\x00\x00";                         
    }

    /**
     * Save the zip file
     *
     * @param string $file file name with path
     */
    public function save($file)
    {
        if($this->old_offset > 0)
        {
            $fp = fopen($file,"w");
            fwrite($fp, $this->file());
            return fclose($fp);
        }
        else
        {
            trigger_error("No file to store in zip file", E_USER_WARNING);
        }
    }
}